Conventionally, there has been known a so-called autonomous-traveling type vacuum cleaner (cleaning robot) which cleans a surface to be cleaned while autonomously traveling on the surface. Such a vacuum cleaner, including a sensor for detecting an obstacle by making contact (colliding) with the obstacle, is under travel control so as to avoid a detected obstacle.
With such a vacuum cleaner as described above, which requires spaces for setting traveling-use driving wheels on both sides of a suction port in a lower portion of the main casing, it is difficult to design a large width of the suction port. Therefore, a cleaning unit such as side brushes is provided so that dust and dirt can be removed over a larger width. In this case, with the side brushes protruding to the side of the main casing, a sensor for detecting an obstacle by such contact as described above cannot be provided at a position of the cleaning unit, giving rise to positions where obstacle detection cannot be achieved. With the side brushes positioned so as not to protrude from the main casing, there arises a difficulty for the side brushes to reach outward of the outer frame of the main casing so that wall proximities or the like cannot be cleaned securely.